Am 19.01.2015 um 16:22 schrieb Artyom Tarasenko: > On Mon, Jan 19, 2015 at 4:01 PM, Andreas Färber <afaer...@suse.de> wrote: >> Am 19.01.2015 um 13:57 schrieb Artyom Tarasenko: >>> On Mon, Jan 19, 2015 at 1:45 PM, Paolo Bonzini <pbonz...@redhat.com> wrote: >>>> On 19/01/2015 12:35, Mark Cave-Ayland wrote: >>>>> Similar to m48t59_init(), add a mem_base value so that NVRAM can be >>>>> mapped via >>>>> MMIO rather than ioport if required. >>>>> >>>>> Signed-off-by: Mark Cave-Ayland <mark.cave-ayl...@ilande.co.uk> >>>>> --- >>>> >>>> Is it really ISA if it's MMIO? In other words, why can't this be a >>>> sysbus device? >>> >>> On physical machines it's EBus, which is pretty much like 8-bit ISA. >>> So, I think modelling it as ISA is closer to to the reality. >>> But out of curiosity, would it be possible to have a sysbus device >>> somewhere in a middle of PCI space? [...] >> >> Why would you want to use a SysBusDevice in the first place? > > Ask Paolo. :-) For me it's only important to have a MMIO device in the > proper address range. > >> I previously discussed with Mark that it should be an EBusDevice, not an >> ISADevice or SysBusDevice. > > Interesting. I can't find this discussion in the list archive.
Hm, am I mixing that up with SBus then? There were some helper functions related to ROM loading being added as context to my suggestion that I thought could become class fields. > Do you suggest to > create EBusDevices for all ISA devices (serial, parallel, keyboard, > floppy) used in sun4u, or only for m48t59? > What would be the advantage of using EBusDevice over ISADevice? For all devices that are in fact EBus devices. The general idea is encapsulation and abstraction - hiding the implementation detail of whether it is internally an ISADevice or something else. Such a patch should be quite trivial. Similarly it gives helper functions and potential class methods a natural place to live. Andreas -- SUSE Linux GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany GF: Felix Imendörffer, Jane Smithard, Jennifer Guild, Dilip Upmanyu, Graham Norton; HRB 21284 (AG Nürnberg)